• Title/Summary/Keyword: Lift-up

Search Result 304, Processing Time 0.033 seconds

A Study on the Performance of the Wing In Ground Effect by a Vortex Lattice Method (와류 격자법에 의한 지면효과익의 성능 연구)

  • Jeong, Gwang-Hyo;Jang, Jong-Hui;Jeon, Ho-Hwan
    • Journal of Ocean Engineering and Technology
    • /
    • v.12 no.2 s.28
    • /
    • pp.87-96
    • /
    • 1998
  • A numerical simulation was done to investigate the performance of thin wings in close vicinity to ground. The simulation is based on Vortex Lattice Method(VLM) and freely deforming wake elements are taken into account for a sudden acceleration case. The parameters covered in the simulation are angle of attack, aspect ratio, ground clearance, sweep angle and taper ratio. In addition, the effect of the wing endplate on the ground effect is included. The wing sections used for present computations are uncambered, cambered and S-types. The present computational results are compared with other published computational results and experimental data.

  • PDF

Analysis of Ambiguous Adverbial Expression Used for Instruction of Positioning Control

  • Hiratsuka, Shigeyoshi;Inooka, Hikaru;Kajikawa, Shinya
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.32.1-32
    • /
    • 2001
  • Up to now, many studies on human-machine interface with voice systems have been reported. However, in these systems, precise instructions are necessary for a robot to execute given tasks successfully. In order to make a robot friendly, more ambiguous instructions with some kinds of degree adverbs (, e.g., "move it a little", "lift it more" and so on, ) will be preferable. Therefore, we analyze the relationship between ambiguous instructions and the characteristics of instructed human motion in positioning task to design human friendly interface systems. Several experimental results show that adverbial expressions are mainly divided into three clusters corresponding to the displacement, and that instructors and perators have several differences in distance sense each other.

  • PDF

Maintenance and Dynamic Behavior of Spherical Bearings under Railway Open-Steel-Plate-Girder Bridges (철도 판형교에서 스페리칼받침의 유지보수 및 동적 거동)

  • Choi, Eun-Soo;Oh, Ja-Tae;Kim, Hyun-Min
    • Proceedings of the KSR Conference
    • /
    • 2007.05a
    • /
    • pp.1450-1459
    • /
    • 2007
  • Line type rigid bearings for Open-Steel-Plate-Girder railway bridges have several problem in service, and they are unstable structurally. Thus, spherical bearings having advanced maintenance capability and device to resistance up-lift are developed and replace the existing ones. A experiment of maintenance for a new placed spherical bearings under real Open-Steel-Plate-Girder bridge is conducted and their good maintenance performance is proved. The dynamic behavior of the bridge is measured and analyzed for the two cases of the existing and replacing bearings. Therefore, the effect of the new spherical bearings on the railway bridge is assessed.

  • PDF

Development of Korean Dairy Industry - Market Milk (한국 유가공업의 발전과 전망 - 시유)

  • Kim, P.J.
    • Journal of Dairy Science and Biotechnology
    • /
    • v.23 no.2
    • /
    • pp.143-148
    • /
    • 2005
  • Korea dairy market has greatly expanded recently by growing up the consumer's demands of high quality of milk products and their functionality due to expanding of well being lift trends. However, life cycle of dairy products is shorter than ever before and low birth rate is a common trend of Korean people. Moreover due to the national economy crisis, most of dairy companies are faced with the pressure of new milk products development and their sales. This paper deals with the development of Korea dairy industry by chronological order and deals with the future applicable new dairy foods and advanced dairy technology.

  • PDF

High order computation on the three dimensional wakes past a circular cylinder (고해상도수치기법에 의한 원형실린더 주위의 3차원 후류유동 특성연구)

  • Lee, Sang-Soo;Kim, Jae-Soo;Kim, Tae-Su
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.622-625
    • /
    • 2008
  • While the research for flow over a circular cylinder has been actively carried out up to the present, it has been known that the flow has not been clarified even now. Various complex flow and aero-acoustic characteristics exist around a circular cylinder such as flow separation, wake and pressure wave propagation. In this paper, research was carried out for wake flow and aeroacoustics over a circular cylinders by using high order, high resolution techniques that are used in two dimensional aero- acoustic analysis. OpenMP parallel processing method was used. For the numerical result, the periodic characteristic of Strouhal Number due to vortex shedding was comparatively analyzed with other experiment values and two dimensional numerical results.

  • PDF

A systematic approach to the control logic design and PLC programming of a industrial lift (산업용 리프트의 제어로직 설계 및 PLC 프로그래밍을 위한 체계화 연구)

  • 박노억
    • Proceedings of the Korean Society of Machine Tool Engineers Conference
    • /
    • 1999.10a
    • /
    • pp.452-457
    • /
    • 1999
  • The recent control system has been changed into the type of PLC(Programmable Logic Controller) control. Up to now, systematic approach of PLC programming or control logic design is not suggested. In this study, the design process of the control logic is systematized and concrete process in each step is suggested. This systematized approach lead developer to be convenient to implement control system. When some error is occurred in the system, this approach enable the developer to analyze the reason of error rapidly and the system is amended according to systematic information of the analysis. The example of control system implementation following this approach is introduced.

  • PDF

THE STUDY ABOUT THE ENDOSCOPE A/V SYSTEM IMPROVEMENT (ENDOSCOPE A/V SYSTEM 개선에 관한 연구)

  • Chae, Young-Han;Park, Hyun-Sang;Cheon, Seung-Min;Kim, Yeong-Seo;Jeon, Seg-Bong;Kwon, Hyuk-Nam
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1998 no.11
    • /
    • pp.102-103
    • /
    • 1998
  • Various Endoscope Video System have been introduced and used at wide fields in our country. But this system doesn't have fuction available for recording of Video and Audio data at a time. So many problems were caused by this point, like loose of data accuracy, time and manpower consumption for re-editing prodedure and so on. For solving these problems, we made and modified some systems considering economical and practical aspects and tried to lift up efficiency of clinical usage.

  • PDF

The Effect of Variable Electric Fields on the PZT Characteristic and Laminate Configuration in LIPCA (LIPCA에 공급되는 전기장의 변화가 PZT 특성과 적층배향에 미치는 영향)

  • Kim Cheol-Woong;Nam In-Chang;Yoon Kwang-Joon
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 2006.05a
    • /
    • pp.397-398
    • /
    • 2006
  • The advanced piezoelectric ceramic composite actuator, which is called LIPCA with the FRP and the optimization of the laminate configuration, was performed to maximize the stress transfer and the fiber bridging effect. This study evaluated the effect of variable electric fields on the PZT characteristic, laminate configuration and fatigue characteristics under the resonance frequency, which meant the largest performance range and the changes of its interlaminar phase were also evaluated by stages. In conclusions, Comparing with the fatigue lift of intact LIPCA, the fatigue life of LIPCA embedded by the artificial delamination was decreased up to 50%. The micro void growth and the coalescence of epoxy were actively made at the interlaminar phase subject to the large tensile stress.

  • PDF

Static Wind Tunnel Test of Smart Un-manned Aerial Vehicle(SUAV) for TR-S4 Configuration (스마트 무인기 TR-S4 형상의 정적 풍동시험)

  • Choi Sung-Wook;Kim Cheol-Wan;Lee Jang-Yeon;Chung Jin-Deog
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.30 no.10 s.253
    • /
    • pp.1012-1018
    • /
    • 2006
  • To evaluate the aerodynamic efficiency of TR-S4 configuration, wind tunnel tests of 40% scaled model were done in KARI LSWT. TR-S4 configuration has different nacelle shape, larger EO/IR camera and aftward wing location compared with TR-S2. Component build-up test after adding each element of model is performed. Also effects of horizontal tail incidences, Flaperon and Aileron deflection. on aerodynamic characteristics are measured. Test results showed that TR-S4 configuration has favorable stability characteristics in longitudinal, lateral and directional for the pitch and yaw motions.

Fluidic Manipulating in Microchannels Using Hydrophobic Patterns (소수성 패턴을 이용한 미세유로에서의 유체 조작)

  • Lee, Sang-Ho;Kim, Yong-Kweon
    • Proceedings of the KIEE Conference
    • /
    • 2000.11c
    • /
    • pp.583-585
    • /
    • 2000
  • This study reports the fluidic handling method using hydrophobic patterns inside PDMS microchannels. In order to obtain hydrophobic patterns, we pattern fluorcarbon(FC) film surfaces by lift-off process. FC films are deposited by spin coating method and plasma polymerization method. Hydrophobic surfaces are used as the barriers to control fluid flow. Injected liquid is spontaneously filled up inside PDMS-microchannels by the capillary action. Liquid flow stops when it meets hydrophobic regions which can be the barrier against fluid flow. Then, again, when liquid is pressurized externally, liquid can move toward another hydrophilic region by external air pressure. Contact angle analyses are performed on fluorocarbon films to estimate the wettability of film surfaces.

  • PDF